Magnetic separator.



P. WRIGHT & G. LAND. MAGNETIC SEPARATOR. APPLICATION-FILED "my 26, 1913.

Patented Dec. 19, 1916.

2 SHEETS-SHEET I.

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draw 7 P. WRIGHT & G. LAND.

MAGNETIC SEPARATOR. APPLICATION FILED MAY 26. 1913.

Patented Dec. 19, 1916.

2 SHEETSSHEET 2- f 6 d a a 64 a I 1% a Q q b w 4 Q. 5 e M Z w a 1?PARVIN WRIGHT AND GORDON LAND, OF SEATTLE, WASHINGTON; SAID LANDASSIGNOR TO SAID WRIGHT. I

MAGNETIC SEPABATOR.

Specification of Letters Iatent. at t 19, 191

Application filed May 26, 1918. Serial No. 769,895.

To all whom it may concern:

Be it known that we, PARVIN WRIGHT and Gonnon LAND, citizens of theUnited States, residing at Seattle, in thecounty of King and State ofWashington, have invented a new and useful Magnetic Separator, of whichthe following is a specification.-

This invention relates to apparatus for "separating magnetic materialfrom sand,

gravel, etc., and the main object of the invention is to provide amagnetic separator which will be capable of operating with wet material.

A further object of the invention is to prevent. non-magnetic materialfrom being picked up along with the magnetic material in the separatingoperation.

Another object of the invention is to pro vide for effective remov-l ofthe magnetic material from the collecting means.

Other objects of the invention will appear hereinafter.

The accompanying drawings illustrate embodiments of our invention, andrefer-- ring thereto:

Figure 1 is a longitudinal section of the apparatus, showing themagnetic collecting means in elevation. Fig. 2 is a longitudinalsection, showing the magnetic collecting means in section. Fig. 3 is aplan view of the machine with portions broken away. Fig. 4 is a planview partly in section of the magnetic devices for producing themagnetic field in the collecting means. Fig. 5

, is a section showin a modified form of the magnetic drum. ig. 6 is alongitudinal section of another form of the apparatus.

The apparatus is mounted on a frame 1 and comprises a table or plate 2adapted to receive the material from a suitable fiume or chute 3, amagnetic collecting means 4 adapted to pick up the magnetic materialfrom said table, a discharge fiume 5 for said magnetic material, and adischarge table or flume 6 for the'non-magnetic material. The machine isshown as adapted for use in separating magnetic material from goldbearing sands and the discharge fiume 6 is shown as a rifile table,being provided with rifiies 7, this table discharging at its lower endonto suitable means indicated at 8 for performing further operationsupon the material for separating gold therefrom.

The receiving table 2 is preferably formed as a shaking table, saidtable 2 being inclined downward from the feed end to the discharge endthereof, and bein mounted on resilient plates or boards 9 ed at theirlower ends to the frame 1, and at their upper ends to the table so as topermit longitudinal reciprocation of the table. Such reciprocation ofthe table is effected by cams or tappets 10 on a shaft 11, said cams ortappets engaging with a bearing plate 12 in rigid connection with thetable 2. The shaft 11 is driven by any suitable means, for example, by apulley 1 L thereon. At the upper end of the table a screen 15 ispreferably provided, said screen being bent down wardly to form aforaminous trough which is retained in position between inclineddownwardly convergent boards 16 and 17,

the boards 16 forming the upper end wall for the table 2, and the boards17 extending across between the side walls 18 of the table 2, leaving aspace or opening 19 below said board 17 for'passage of the screenedmaterial. The board 1-7 extends obliquely across the table 2 so that thetrough formed by screen 15 has sufiicient downward inclination towardone end to cause the sand accumulated on said screen to gradually worktoward one end of the trough and an opening 20 is provided at that endthrough which such material is discharged. Near the lower end of thetable 2 is provided a screen or forami Said cylinder may be of anysuitable construction adapted to' present magnetic poles of suflicientintensity. The construction which we have found suitable for this purpose is shown in the drawing and consists of a series of magneticelements arranged on a shaft 22; journaled in bearings 23 on the frame1; each of said magneticelements tending from said cores longitudinallywith respect to the shaft 22. The pole-pieces 24 of adjacent magneticelements, extend in onposite directions; and the cores of said elementsare in staggered relation, so that the pole-pieces of adjacent elementsoverlap. Said cores are-provided with windings 26 connected to an ener'zing circuit, in such manner that the ad acent pole-pieces aremagnetized oppositely. A casing is provided for the magnetic cylinder,consisting of a cylinder 28 of copper or other nonmagnetic material,surrounding the series of magnetic elements, and heads 29 of nonmagneticmaterial, brazed or otherwise secured to said cylinder 28; a hole 30being left in one of said heads, through which suitable insulatingmaterial, such as pitch, is run into the cylinder, to completely fillthe same and form, when said material is solidified, a solid, waterproofbody. The wires 31 connected to the windings for the magnetic elements,are carried through a longitudinal bore 33 in the shaft 22, and areconnected to collector rings 34 on said shaft. Brushes 35 contact withsaid collector rings, and are connected by wires 36 to an electricgenerator 37 driven by any suitable means. Shaft 22 for the magneticdevice is driven by any suitable means, for example, by belt and pulleyconnection 63, 64 and 65 from shaft 11 aforesaid. Any other suitableconstruction of the magnetic device may be used, for example, as shownin Fig. 5. The same may consist of cylindrical armature body 38 of ironhaving longitudinal slots 38 for receiving the magnetizing windings 39,which are wound on said body so as to develop magnetic poles at thesurface of said body, the said body and coils being inclosed in acylindrical casing 28. The cylinder s0constructed is mounted to rotatein the machine in the manner above described.

An endless, flexible conveyer member, consisting, for example, of anendless canvas belt 40, extends around the cylinder 28, and around aroller 41 mounted-in bearings 42 on a fiume 5, which is pivotallysupported on a pipe 45, extending transversely through the delivery ordischarge flume 6, the mounting being such that the said fiume 5 acts asa thrust member and the belt 40 acts as a tensible member whereby thebelt is tensioned bythe wei ht of the flume 6, the roller 41 and thebelt itself. The bear-.

ings 42 are preferably adjustable to regulate the tension of the beltand the distance between the lower run of the belt 40 and the fiume 5,said bearings bein for example, formed in the upper ends 0 levers 50,pivoted at 51, on the sides of the flume 5 and adjusted by set screws 52screwing through said pipe being connected to any suitable source ofwater supply, under definite head, and having perforations 58 throughwhich water is discharged into a box 49 at the upper end of the fiume 5,the upper edge of said box serving as a spillwa over which any surpluswater will flow ectly .to the fiume 6, the rest of the water flowingover the lower edge ofsaid box and down al'on the flume 5. The fiume 5dis charges at 1ts lower end into a chute 60 for conveying themagneticmaterial to any desired place.

The operation is as follows: The sand or gravel which has been screenedin asuitable manner so as to remove the coarse gravel and bowlders, isdelivered together with water by the fiume 3 to the screen 15 whichallows only the sand to pass under the table 2, all the coarsermaterials passing through the outlet 20, the sand passing through thescreen including not only the ordinary silica sand and other non-ma eticsand, but also including any black san that may be present in thedeposit which is being worked, this black sand consisting generally ofmagnetite, but also comprising in some cases chromite, monazite andother magnetic materials. Any finely divided gold the table. The shakingmotion ofthe table in conjunction with the action of the water passingalong with the material also tends to stratify the material to someextent, the black sand and the gold,platin'um, etc., if any be present,accumulatin in a lower layer and the lighter materia s tending topass'along the top of the bed of material on the table 2. The black sandtherefore tends to as beneath the screen 21, said screen 21 d eingspaced above the table 2 a suflicient distance to permit ofsubstantially all of the black sand passing beneath the same.Thecylinder 4 being set in rotation and the magnetic, devices thereinbeing energized by curre tjirom the generator 37,. a strongmagnetic-field or a series of magnetic fields is produced' idirectlyabove the screen 21, causing the particles of magnetic material belowthe screen to be drawn up through the meshes of the screen, such meshesinsuring that the particles will be picked up individually and not inthe form of chains or bunches. For this reason only the'magneticparticles are drawn up to the cylinder 4 and said cylinder doesnot pickup any nonmagnetic particles entangled with such magnetic particles. Theparticles so picked up accumulate against the canvas belt 40, being heldagainst said belt by the magnetic attraction due to the fields betweenthe pole-pieces for the magnetic devices in this cylinder. In themovement of the belt, the portions of the belt carrying themagnetizedparticles eventually pass away from the cylinder on enteringthe upper straight run of the belt and are thereby removed from themagnetic fields produced by the cylinder. These particles are carrieddown by the belt and over the lower roller which is partly immersed inwater flowing downwardlyin the flume 5 from the supply pipe 45. Thecurrent of water passing down the flume from this supply pipe tends tosweep ofl any particles of magnetic material that may adhere to the beltand to carry the same down the flume 5, such magnetic material beingdischarged through the discharge flume chute 60.

The invention has especial adaptability to the separation of magneticmaterial from gold bearing sands so as to facilitate the subsequenttreatment of the sand in the separation of gold therefrom, and in suchconnection we prefer to use the .form of riflies shown in Figs. 1 and 2,said riflles consistingof angle bars having their .upper faces extendingobliquely upward and forward with reference to the riflie floor, thisconstruction causing the water and sand as they pass over the riflie tobe given an eddying motion which tends to keep the rifile spaces clearedand prevents clogging thereof.

In cases where the magnetic material comprises several diflerentconstituents, such for example, as magnetite, chromite, and monazite, weprefer to provide for separation of such different constituents from oneanother, and in that case the construction shown in Fig. 6 may beadopted, the same comprising a series of shaking tables 2, 2", 2", eachprovided with a screen 21, said tables being preferably connectedtogether and mounted to reciprocate in unison, and the last tabledischarging onto a rifi'le table 7. At the lower end of each of thetables 2 is provided a magnetic collecting device 4, 4", 4; having abelt 40 and a washing flume 5 is pro.- vided for clearing the belt ofeach magnetic device. The respective magnetic collecting drums areconnected to branch circuits 61 of an energizing circuit 62, said branchcircuits including rheostats 63 to enable the current through therespective magnetic devices 4 4", 4, to be regulated independently. Bysuch regulation or by making the magnetic devices of differentresistance, the magnetic device 4 is made to present stronger magneticaction than the device 4, and the device 4 is made to present strongermagnetic action than the device 4. The operation of this form of theinvention is as follows: The material supplied to the first shakingtable 2 is brought under the first wmagnetic collecting device 4* and isthere subjected to magnetic field sufficientto' pick.

up the more readily magnetizable constituents, for example, themagnetite which is thereby removed from the body of sand and dischargedthrough the first discharge means 60. The remaining material passesbeneath the second magnetic separating device 4 whereby it is subjectedto a stronger magnetic field, causing another constituent, for example,the chromite, to be picked up and separated, this operation beingrepeated, subjecting the material'at each operation to a stronger fieldso as toseparate the different constituents. g

WVhat we claim is: I

1. In a magnetic separator, a material receiving table, a cylindermounted to rotate adjacent said stable and provided with magneticdevices for producin magnetic poles at the periphery of said cy inder,means for supplying material and water to said table, means forconveying away the discharge from said table, a flume mounted over saiddischarge means, a roller journaled on said flume, and a belt passingaround said cylinder and said roller to convey the magnetic materialfrom said cylinder to said flume, said flume being pivotally mounted sothat its weight is sustained by said belt and tensions the belt.

2. In a magnetic separator, a material receiving table, a cylindermounted to rotate adjacent said table and provided with mag neticdevices forproducing magnetic poles at the periphery of said cylinder,means for supplying material and water to said table, means forconveying away the discharge from said table, a flume mounted-over saiddischarge means, a roller journaled on said flume, a belt passing aroundsaid cylinder and said roller to convey the magnetic material .from saidcylinder to said flume, said flume being pivotally mounted so that itsweight is sustained by said belt and tensions the belt, and means foradjusting the ends of said roller relatively to said cylinder.

3. In a magnetic separator, a material re ceiving table, a cylindermounted to rotate adjacent said table and provided with magnetic devicesfor producing magnetic poles at the periphery of said cylinder, meansfor supplying material and Water to said table, means for conveying awaythe discharge from said table, a flume mounted over said dischargemeans, a roller journaled on said flume, a belt passing around saidcylinder and said roller to convey the magnetic material from saidcylinder to said flume, said fiume being pivotallymounted so that itsset ourflhands at Seattle, Wash.,-on this 21st weight is sustained bysaid belt and tensions day of May, 1913. v i the belt, and a watersupply pipe on which PARVIN WRIGHT. said fiume is 'pivotally mounted,provided GORDON LAND. 5 with openings ,for discharging water into Inpresence ofsaid fiume. J. B. MAGHANS,

In testimony whereof, we have hereunto JONATHAN Gmro m.

